An electric vehicle is a vehicle which is propelled by an electric motor. The electric motor draws its power from a battery which is housed in the electric vehicle. This battery needs to be charged again after a discharge. For charging the battery, a charging device is used in the sense of the present invention. The charging device can be a part of the electric vehicle or a part of a charging station. If the battery of an electric vehicle is to be charged, the charging device of a charging station is connected mechanically and electrically with the charging device of an electric vehicle. Then, the battery can be charged by means of an electric current supplied by the charging station.
To avoid an unauthorized access during the charging of a battery of an electric vehicle, the mechanical and electrical connection between two charging devices must be locked during this time. A suitable locking device which is able to protect against unauthorized removal of the charging plug is disclosed in the publication DE 196 42 687 A1. For this purpose, this locking device comprises a control element for adjusting a bolt for the purpose of locking the charging plug. In order to provide a locking action, the bolt passes into a retaining opening.